Aristotle's Physics
There is quite a lot of words in the Physics. In a way, that's surprising: my mental image of those days is that paper3 wss in short supply, so you'd expect authors to have thought carefully before writing and to have compressed their work. Instead, A does the reverse: is discoursive and repetitive and doesn't follow a clear sequence. In this - as with the Politics - one gets the impression of a poorly edited collection of lecture notes. What it doesn't read like is ideas that have survived testing by rigourous dialectic.
Perhaps the greatest virtue of the work is as an example: that something that has survived for a long time can still be completely wrong, and yet still be defended. Consider what other ideas we see in the world today are similar. Of course, part of the problem is that anyone inclined to study this stuff deeply is going to be in sympathy with the material; no-one is going to waste much time ripping it to shreds. So why - I hear you ask - am I bothering? Well I've had these volumes on my shelves for many years now, and the time has finally come to finish reading and dispose of them.
Like say Hippolytus or Iphigenia in Tauris this comes into the "it lasted 2,000 years so there must be something worth while in it" but unlike them it is not literature; and it has not fared well. In the following I shall assume that the (English) words I'm reading have captured the original meaning of the text, despite the gulf that separates us; given the contortions that his translators and interpreters have gone through, I think it likely that I'm getting his best shot, or perhaps better than.
A discusses, let us say, motion. And he is smart enough to try to abstract; he is not interested in the motion of any individual ox-cart. Unfortunately, he abstracts all the way to abstraction; which I can best explain by comparing to, say, Galileo's experiments with rolling spheres down inclined planes. That abstracted to a concrete reality, and so was able to learn something, by observing how very simple entities behave. A abstracts out everything but movers and moving, and so is unable to learn anything.
A is interested in both the real world - or at least, in an abstract version thereof - and in the world of mathematics. Unfortunately he rarely distinguishes the two, or says which any given discussion appertains to; so much so that I doubt he has the distinction clearly in his mind. He is, however, aware that there is a distinction2.
In trying to think about how to Do Physics, A starts well Hence, in advancing to that which is intrinsically more luminous and by its nature accessible to deeper knowledge, we must needs start from what is more immediately within our cognition, though in its own nature less fully accessible to understanding. Now the things most obvious and immediately cognizable by us are concrete and particular, rather than abstract and general; whereas elements and principles are only accessible to us afterwards, as derived from the concrete data when we have analysed them. So we must advance from the concrete whole to the several constituents which it embraces; had he stuck to this, he would have fared much better. That's book I chapter I; chapter II starts off wondering how many "principle"s or "primary constituents" there are; attempting to translate this into ModernSpeak, it seems likely that he is wondering how many elements there are (rather than fundamental particles or states of matter) but - characteristically - his discussion is so unanchored by reality that one cannot really tell; he is already lost, and doesn't know it. He deduces that there must be either one, or finitely many, or infinitely many; after that he bogs down; then chapter VI concludes It is clear, then, that there must be more than one element or principle, and that there cannot be more than two or three. But, within these limits, the decision as between two and three presents great difficulties. This is based on "logic" along the lines of we need a pair of antithetical qualities; and (for the third, if needed) they need something to act on. So alas despite his declared intent to start with reality he falls at the first hurdle, and is reduced to being either Wrong, or perhaps Not Even Wrong. To the obvious rebuttal (which will come up time and again) "but in those early days it was really hard to know anything" comes the obvious answer: yes, it was. And so A, if honest, would have concluded that he simply didn't know and couldn't say anything useful on the topic. To some extent, supported by the end of book I, I believe that A was in this section merely surveying other opinions of the time, or felt himself unable to avoid opining. And sadly book II chapter I begins by stating that the elementary substances are earth, fire, air and water; see previous comments re badly edited lecture notes. Nothing else of interest appears in book II. I should perhaps note that there's quite a lot of stuff that my eyes just slide off... all the verbiage about causes for example; he does love classifying things, even if he has to make them up to do so.
Book III begins by defining motion; I took the piss out of that some years ago and don't feel much more merciful now. His problem is not realising that some things are better left undefined, as Newton did with time; we all know what it is (errm) so wrapping a pile of complicated words around a simple idea doesn't help; see-also Popper. That said, he is also covering too broad a scope; had he restricted himself to physical motion of inanimate objects he might have got along better.
Chapter IV begins to talk about infinity; but in the context of Nature (and thus, implicitly, not Maths).
[I'm fairly sure I intended to write more, but realised that it was all drivel anyway, and badly organised at that. I did Aristotle and the continuum before.]
Refs
* Paul Graham: how to do philosophy.
* Russell on Aristotle's Politics5.
* My Left Kidney - ACX.
Notes
1. Although to be fair, generally not about his Physics. The sort of defensive thing you can expect supporters to say about the Physics is along the lines of What, then, are we to expect from the Physics ? Something that is still of philosophical interest; very much that is of historic interest and that has entered deeply into the texture of our language; much of purely intellectual interest and bracing gymnastic; but also much that is of vital significance in relation to that borderland between physical and metaphysical thought where mathematics and philosophy meet, which I quote from the Loeb intro. Notice that they cannot even begin to mention that so much of it is wrong.
2. From book II chapter II: we have next to consider how the mathematician differs from the physicist or natural philosopher; for natural bodies have surfaces and occupy spaces, have lengths and present points, all which are subjects of mathe matical study. And then there is the connected question whether astronomy is a separate science from physics or only a special branch of it; for if the student of Nature is concerned to know what the sun and moon are, it were strange if he could avoid inquiry into their essential properties; especially as we find that writers on Nature have, as a fact, discoursed on the shape of the moon and sun and raised the question whether the earth, or the cosmos, is spherical or otherwise. Physicists, astronomers, and mathematicians, then, all have to deal with lines, figures and the rest. But the mathematician is not concerned with these concepts qua boundaries of natural bodies, nor with their properties as manifested in such bodies. Therefore he abstracts them from physical conditions; for they are capable of being considered in the mind in separation from the motions of the bodies to which they pertain, and such abstraction does not affect the validity of the reasoning or lead to any false conclusions.
3. Or equivalent.
4. Descartes is lead to this error by his idea that the "essential" property of a given object is its extension in space, which causes him to think in these terms; presumably, an indivisible object would have a property-in-itself that wouldn't fit into his schema. In turn this leads him to fail to get to momentum, despite some promising thoughts in that area. But analysing his errors individually isn't really interesting; my point rather is that there are endless ways of going wrong; you will always fall off the knife-edge of truth, unless you have something - in the case of physics, reality - to correct you.
5. Russell on Aristotle's logic: I conclude that the Aristotelian doctrines with which we have been concerned in this chapter are wholly false, with the exception of the formal theory of the syllogism, which is unimportant. Any person in the present day who wishes to learn logic will be wasting his time if he reads Aristotle or any of his disciples.
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